AUGUSTA (AP) – State police have asked about a dozen environmental activists in Maine to provide samples of their DNA as part of an ongoing criminal investigation, police said.

Most of those asked did not comply, according to a report by Maine Public Radio, but now the DNA request is raising concerns about whether government is trying to stifle activism and free speech.

In April, members of the environmental activist group Earth First! planned to camp on Sears Island, in defiance of a ban on camping on the state-owned property. But after police searched the island and confiscated equipment found there, the activists decided to camp on private land off the island.

There was some interaction between police and activists on a causeway that links the island to the mainland, but there were no arrests or citations, and police returned the camping equipment.

But a month later, state police officers knocked on the doors of about a dozen people they identified as linked to the Sears Island events. They had an unusual request: a DNA sample.

“It was totally voluntary,” state police spokesman Steve McCausland told Maine Public Radio on Wednesday. “A couple said yes.’ Most said no.”‘

McCausland said the requests for DNA samples were made as part of ongoing investigations, although he declined to say what investigations those were.

Asked whether the requests were related to a vandalism episode last year at the offices of the Plum Creek development company, McCausland declined comment.

Plum Creek has drawn the ire of some environmental organizations with its proposal of a large-scale development for the Moosehead Lake region.

Attempts to contact people who police asked to provide DNA went unanswered on Wednesday.

But a lawyer representing some of them, Philip Worden, said police were casting an over-wide net.

“This does have all the hallmarks of a classic fishing expedition,” Worden said. “And obviously the courts do not approve of that if there’s any kind of interference with Fourth or Fifth Amendment rights.”

The Fourth Amendment to the U.S. Constitution protects against unreasonable searches and seizures, and the Fifth protects against self-incrimination. Worden said the DNA requests in some cases made the subjects feel intimidated.

“My own main concern isn’t just with the people that were asked,” Worden said. “It’s the chilling effect on everybody else. If you get the idea that just because somebody attended a legal environmental meeting, that by doing that the state police might show up at your doorstep, ask for a DNA sample as though you might be suspected of some sort of terrorist activity … that’s going to scare people.”

Worden and others said police did not appear to have done anything illegal simply by asking for the DNA samples. But the practice is raising civil rights concerns.

Shenna Bellows, executive director of the Maine Civil Liberties Union, said that DNA samples – usually obtained through a mouth swab – provide much more comprehensive information about a person than does a fingerprint.

“The police have the right to ask, perhaps,” Bellows said. “But it’s a question of whether people then feel coerced to comply with that request, and I think most people probably wouldn’t realize they have the right to say no.”

McCausland, of the state police, said police are likely to retain the two DNA samples already obtained. He emphasized, however, that they had been provided voluntarily.

“You can’t blame us for asking,” McCausland said.

AP-ES-06-08-06 0216EDT